Urea pump module for vehicles

Abstract

Urea pump module for vehicles, comprising: a housing (10) comprising a partition plate (13) with a urea outlet opening (11) and a plurality of tubes (12) formed in an upper surface thereof, as well as an upper and a lower protective plate (14, 15) which are integrally formed at the upper and lower surface edge of the respective partition plate (13); a cylindrical heating device (20) comprising a first sealing material (23) which is injected over a surface of a cylindrical cooling element (21) coupled to a positive temperature coefficient (PTC) element (22), wherein the heating device (20) has a first fastening opening (24) in an outer circumferential section into which each tube (12) is inserted and fastened; an electric motor (30) comprising a second sealing material (34) which is injected over a surface of a hollow stator (33), wherein a winding runs around an outer circumferential section of the same, and a terminal is provided on its upper side, and wherein the electric motor (30) has a second mounting opening (35) in the outer circumferential section, such that an upper end section of the tube (12) which has been passed through the first mounting opening (24) is inserted into and secured in the second mounting opening (35); and a pump (40) with a rotor (41) rotatably mounted on its upper side, which is inserted into the hollow stator (33) of the electric motor (30), an inlet opening (42) and an outlet opening (43) in a lower section, and a pair of gears (46) rotatably installed therein in forward or reverse rotation, wherein in a state in which the electric motor (30) and the pump (40) are inserted and arranged in a hollow section of the heating device (20), heat from the heating device (20) is transferred to the electric motor (30) and the pump (40) as well as to the urea in the urea tank.

Description

BACKGROUND(a) Technical field

[0001] The present disclosure relates to a urea pump module for vehicles and in particular to a urea pump module for vehicles configured to supply urea to a selective catalytic reduction (SCR) system of a diesel vehicle. (b) Description of the related technique

[0002] The exhaust system of a diesel-powered vehicle is equipped with a selective catalytic reduction (SCR) system that sprays urea into an exhaust pipe to effectively remove nitrogen oxides.

[0003] For this purpose, the diesel-powered vehicle (especially a commercial vehicle) is equipped with a diesel fuel tank filled with diesel fuel, as described in... Fig. Figure 18 (RELATED TECHNOLOGY) is shown equipped with a urea tank 1 filled with urea, and a urea pump module 2 is installed in the urea tank 1 for pumping urea to supply the urea to the SCR system.

[0004] Therefore, when the urea from the urea tank 1 is supplied by pumping the pump module 2 to a urea dosing module 3, which is an injector installed in the inlet of an SCR catalyst 4, the urea dosing module 3 sprays urea to the SCR catalyst 4 in order to reduce the amount of NOx.

[0005] In this process, the urea sprayed onto the SCR catalyst 4 is broken down by the exhaust gas heat into a large number of ammonia molecules, which react with the nitrogen oxide (NOx) in the exhaust gas, and harmless nitrogen (N2) and water (H2O) are discharged to the outside as reaction products.

[0006] As described above, the urea pump module used in the SCR system is designed and built to deliver a required amount of urea at constant pressure from the urea tank to the urea dosing module 3 as an injector and to take back the urea when the ignition is switched off to prevent freezing of a urea line.

[0007] Furthermore, the urea pump module is designed and built to include, for example, a heating function to thaw urea if it is frozen in the urea tank to ensure normal urea feeding, a fill level sensing function to detect the remaining amount of urea in the urea tank and send the result to a controller, a temperature sensing function to detect the temperature in the urea tank and send the result to the controller, a filtration function to remove foreign substances contained in the urea, and a urea concentration sensing function to detect an impermissible urea concentration when introducing the urea.

[0008] However, a conventional urea pump module, as shown in the diagram, is Fig. The 18 problems described above are associated with the following issues.

[0009] Firstly, due to, for example, the formation of cracks as a result of the deterioration of the strength of a urea pump housing, the urea can penetrate into a pump drive unit (e.g., into a stator and rotor of an electric motor), into a circuit element of a heating device to prevent the urea from freezing, and into various sensors, thereby damaging the urea pump and consequently causing it to stop operating.

[0010] Secondly, in winter, due to insufficient performance of the heating system to prevent the urea from freezing, the urea cannot be properly thawed, resulting in an increase in the amount of exhaust gas (NOx).

[0011] This means that the SCR system is characterized by an undefined timing of the urea injection and the amount of sprayed, which results in an increase in the amount of exhaust gas (NOx) due to pulsation.

[0012] Furthermore, if the urea is not properly thawed due to insufficient performance of the heating device to prevent the urea from freezing, an element in a urea line of the entire pump module may be damaged.

[0013] Thirdly, if urea enters a urea concentration sensor, which is an ultrasonic sensor, the precision of the urea concentration sensor's detection, i.e., the precision of a concentration level output by the reflection of the received waves, may deteriorate.

[0014] Fourthly, an electric motor can be damaged by shocks caused by magnetic force when the rotor forming the electric motor of the urea pump module is installed.

[0015] Fifthly, the conventional urea pump module contains a total of two pumps, namely a urea delivery pump and a urea return pump, which results in a complicated structure of the pump module and higher manufacturing costs.

[0016] Furthermore, in the conventional urea pump module, due to the deterioration of the filtration function of foreign substances from the urea, the foreign substances concentrate in a specific area of ​​the urea flow path, which causes a deterioration in the durability and service life of the urea pump module, and main elements of the urea pump module are assembled by thermal connection, which results in a deterioration in productivity and an increase in scrap.

[0017] In this context, DE 10 2013 112 474 A1 discloses a urea solution pump unit with a rotor with a rotor fitting that covers an iron rotor core and a rotor magnet, which are arranged on an outer circumference of a rotor shaft to seal them, a stator in which a stator body is arranged to form a sealed fluid flow space between an outer circumference of the rotor and its inner circumference, wherein an iron stator core is arranged on an outside of it and wherein a stator wire is wound around the iron stator core.A first stator fitting is formed to seal the stator wire, and a second stator fitting is formed to seal the first stator fitting and the iron stator core, as well as a pump which is mounted on an inner circumference from one side of the second stator fitting, and which draws in fluid from the outside by rotating the rotor shaft in order to pump the fluid to a gap between the rotor fitting and the stator body, the fluid which is pumped by the pump being discharged through an outlet passage which is formed on the other side of the stator body.

[0018] DE 10 2012 106 844 A1 discloses a structure of a urea solution pump, comprising a housing section (100) connected to an external connector and covering an upper section of the pump structure, a motor section arranged on a lower section of the housing section (100) and comprising a rotor and a stator, an enclosure section enclosing the motor section therein, and a pump section arranged on a lower section of the enclosure section and fluidly isolated from the motor section, wherein the pump section is provided with an inlet and an outlet for a fluid, wherein a hollow cover is provided on a lower section of the enclosure section for separating the pump section and the motor section from each other, and an oil sealing unit is mounted on a lower section of the hollow cover for sealing a rotating shaft of the rotor penetrating the hollow cover.

[0019] Furthermore, a heating structure is known from EP 3 263 861 A1, which serves to heat a pump installed in a tank in order to pump a liquid stored in the tank to the outside. The heating structure comprises a flange installed on one side of the inside of the tank; and a heating element coupled to one side of the flange and provided on that side with a receiving groove in which at least part of the pump is housed, wherein a first outlet pipe of the pump, at least part of which is housed in the receiving groove, extends towards the flange and is connected to a second outlet pipe formed on the other side of the flange outside the tank, and the heating element is configured to heat at least part of the pump, the first outlet pipe and at least part of the second outlet pipe. SUMMARY

[0020] One objective of the present disclosure is to provide a urea pump module for vehicles which, for example, has a structure that can prevent urea from entering electrical elements such as a pump, a heating device and a sensor of the urea pump module, a structure that easily thaws frozen urea, a structure for separating foreign substances, a structure for reducing vibration noise, a structure with which urea can be discharged and drawn in by means of a single pump, and a structure with which assembly efficiency can be increased by means of a lighter assembly of the respective elements.

[0021] In one aspect, a urea pump module for a vehicle comprises: a housing containing a partition plate with a urea outlet opening and a plurality of tubes formed in an upper surface thereof, as well as an upper and a lower protective plate integrally formed at the upper and lower surface edges of the respective partition plate; a cylindrical heating device comprising a first sealing material injected over a surface of a cylindrical heat sink coupled to a positive temperature coefficient (PTC) element, the heating device having a first mounting opening in an outer circumferential section into which each tube is inserted and secured;an electric motor comprising a second sealing material which is sprayed over a surface of a hollow stator, wherein a winding runs around an outer circumferential section of the same and a terminal is provided on its top side, and wherein the electric motor has a second mounting opening in the outer circumferential section such that an upper end section of the tube which has been passed through the first mounting opening is inserted into and secured in the second mounting opening;and a pump with a rotor rotatably mounted on its upper side, which is inserted into the hollow stator of the electric motor, an inlet and outlet in a lower section, and a pair of gears rotatably installed therein in forward or reverse rotation, wherein, in a state in which the electric motor and the pump are inserted and arranged in a hollow section of the heating device, heat from the heating device is transferred to the electric motor and the pump, as well as to the urea in the urea tank.

[0022] In a preferred embodiment, the partition plate of the housing can have a lower surface to which a circuit board for processing signals from a urea fill level sensor and a sensor for detecting an impermissible urea concentration is attached, and the lower protective plate can have a connector for the input / output of the circuit board and an auxiliary urea connection that communicates with the urea outlet opening.

[0023] In another preferred embodiment, the lower protective plate can be connected to a sealing cover that seals electronic elements on a lower surface of the separating plate and in the lower protective plate, and the sealing cover can have a vent of the check valve type.

[0024] In a further preferred embodiment, the first sealing material can have a first injection-molded section that is first injected onto a section of an inner circumferential surface and an outer circumferential surface of the cylindrical heat sink coupled to the PTC element, and a second injection-molded section that is then injected onto an upper surface and the remaining inner circumferential surface of the heat sink, and a contact surface with a toothed structure can be provided between the first and the second injection-molded section.

[0025] In another preferred embodiment, a contact surface with a toothed structure can be provided between the second sealing material and a lower surface of the hollow stator.

[0026] In another preferred embodiment, the pump may include a third sealing material that is injected over a surface of the rotor, and an E-ring may be fitted at the top end of a rotating shaft that protrudes from an upper surface of the rotor to prevent the rotor from coming loose.

[0027] In another preferred embodiment, the gears can have a bypass line at their center of rotation for communication with the interior of the urea tank, the bypass line serving as a path for the reduction of the remaining high pressure when the gears installed in the pump rotate forward or backward.

[0028] In a further preferred embodiment, the filter assembly can include a housing with an open outer circumferential section that communicates with the urea inlet formed in the upper protective plate, wherein the housing is formed with an upper open structure for the filter assembly and rests on and is assembled with a side section of the upper surface of the separating plate, a filter formed by overmolding on a bottom of the housing, an upper cover tightly assembled with an upper opening in the housing that covers the filter, and a suction tube that protrudes from an inner diameter section of the housing and communicates with a space in the housing after filtration by the filter, wherein the suction tube is connected to the intake opening in the pump.

[0029] In a further preferred embodiment, a urea fill level sensor and a sensor for detecting an impermissible urea concentration can be installed on the upper surface of the separating plate at independent positions such that the urea fill level sensor sends and receives ultrasonic waves in a vertical direction and the sensor for detecting an impermissible urea concentration sends and receives ultrasonic waves in a horizontal direction.

[0030] In another preferred embodiment, the urea fill level sensor can include a cylindrical guide configured to guide the sending and receiving of the perpendicular ultrasonic waves, and the sensor for detecting an impermissible urea concentration can include an ultrasonic wave emitter and a reflector arranged opposite each other on the partition plate.

[0031] In a further preferred embodiment, the first sealing material sprayed onto the surface of the heating device and the second sealing material sprayed onto a surface of the electric motor can contain a plurality of ribs with a round cross-section on their upper surfaces to prevent the reflection of the ultrasonic waves emitted by the urea fill level sensor and reflected by a urea flow plane.

[0032] In a further preferred embodiment, the pump can include a first rubber element with a ring shape, which is attached to a lower surface of the same and is in contact with the upper surface of the separating plate to absorb vibrations, and a second rubber ring can be attached to a contact section between an upper surface of the cylindrical heating device and the electric motor during assembly.

[0033] Other aspects and preferred embodiments of the disclosure are explained below. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The above and other features of the present disclosure are now described in detail with reference to certain embodiments, which are shown only by way of example in the accompanying drawings, and thus do not limit the present disclosure; they show: Fig. 1 a perspective top view of a urea pump module for vehicles according to the present disclosure; Fig. 2 a perspective view from below of the urea pump module for vehicles according to the present disclosure; Fig. 3 a perspective view showing the assembly process of the electric motor of the urea pump module for vehicles according to the present disclosure; Fig. 4 a sectional view showing the installation state of the electric motor of the urea pump module for vehicles according to the present disclosure; Fig. 5 a perspective view showing the installed state of the pump of the urea pump module for vehicles according to the present disclosure; Fig. 6A and Fig. 6B Perspective views showing the common installation state of an electric motor and a pump of the urea pump module for vehicles according to the present disclosure; Fig. 7 a perspective view showing the assembly process of a heating device of the urea pump module for vehicles according to the present disclosure; Fig. 8 a sectional view showing the installed state of the heating device of the urea pump module for vehicles according to the present disclosure; Fig. 9 a perspective view showing a filter assembly process of the urea pump module for vehicles according to the present disclosure; Fig. 10 a perspective view showing the entire assembly process of the urea pump module for vehicles according to the present disclosure; Fig. 11 a sectional view showing the internal structure in the assembled state of the electric motor and pump of the urea pump module for vehicles according to the present disclosure; Fig. 12 a sectional view of the flow during pump operation of the urea pump module for vehicles according to the present disclosure; Fig. 13 a sectional view showing the installation state of the heating device of the urea pump module for vehicles according to the present disclosure; Fig. 14 a perspective view of the filter flow of a filter in the urea pump module for vehicles according to the present disclosure; Fig. 15 a perspective view showing the installation state of various sensors of the urea pump module for vehicles according to the present disclosure; Fig. 16 a perspective view of the anti-reflection structure of a signal from an ultrasonic sensor of the urea pump module for vehicles according to the present disclosure; Fig. 17 a perspective view of the vibration damping structure of the urea pump module for vehicles according to the present disclosure; and Fig. 18 (RELATED TECHNOLOGY) a schematic view of the configuration and operation of a conventional SCR system.

[0035] It is understood that the accompanying drawings are not necessarily to scale, as they show a somewhat simplified representation of the various preferred features that are exemplary for the basics of the disclosure. The specific design features of the present disclosure, which include, for example, certain dimensions, orientations, locations, and shapes, are partly determined by the particular intended application and the environmental conditions at the place of use.

[0036] In the figures, identical reference numerals denote identical or equivalent parts of the present invention in the different figures of the drawing. DETAILED DESCRIPTION

[0037] It is understood that the term "vehicle" or "vehicle-related" or other similar terms used herein generally refer to motor vehicles, such as passenger cars, including sports utility vehicles (SUVs), buses, trucks, various commercial vehicles, personal watercraft including various boats and ships, aircraft, and the like, and also includes hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles (rechargeable from an electrical outlet), hydrogen-powered vehicles, and other vehicles powered by alternative fuels (e.g., fuels derived from resources other than petroleum). As used herein, a hybrid vehicle is a vehicle with two or more sources of propulsion, e.g., vehicles powered by both gasoline and electric motors.

[0038] The terminology used herein is intended to describe only certain embodiments and is not meant to limit the disclosure. As used herein, the singular forms "one" and "the" are to include the plural forms unless the context clearly indicates otherwise. Furthermore, it is understood that the term "has" and / or "having" as used in this description indicates the presence of specified features, integer quantities, steps, operations, and / or components, but does not exclude the presence or addition of one or more other features, integer quantities, steps, operations, elements, components, and / or groups thereof. As used herein, the phrase "and / or" includes all combinations of one or more of the listed items.Unless expressly stated otherwise, throughout this description the term "constitute" and forms thereof such as "constitutes" or "constitutes" are to be understood as including the specified elements, but not excluding other elements. Furthermore, the term "unit," the (English) endings "-er" and "-or," and the term "module" in this description mean units for processing at least one function and operation and may be implemented by hardware or software components and combinations thereof.

[0039] Furthermore, the control logic of the present invention can be implemented as non-volatile, computer-readable media on a computer-readable medium containing executable program instructions that are executed by a processor, controller, or the like. Examples of computer-readable media include, but are not limited to, ROMs, RAMs, compact discs (CD)-ROMs, magnetic tapes, floppy disks, USB flash drives, smart cards, and optical data storage devices. The computer-readable recording medium can also be distributed across networked computer systems, allowing the computer-readable medium to be stored and executed in a distributed manner, for example, by a telematics server or a controller area network (CAN).

[0040] In the following, exemplary embodiments of the present disclosure are described in detail with reference to the accompanying drawings.

[0041] Fig. Figure 1 is a perspective top view of a urea pump module for vehicles according to the present disclosure and Fig. Figure 2 is a perspective view from below of the urea pump module for vehicles according to the present disclosure.

[0042] In the Fig. 1 and Fig. 2 indicates reference numeral 10, a plastic housing.

[0043] The housing 10 contains a partition plate 13 with a urea outlet opening 11 and a plurality of tubes 12 in the upper surface, as well as an upper and a lower protective plate 14 and 15, which are integrally formed on the upper and lower surface edge of the partition plate 13.

[0044] The upper surface of the partition plate 13 and the upper protective plate 15 form a space in which a heating device 20, a pump 40 with an electric motor 30 and a filter assembly 50 are installed one after the other.

[0045] In particular, when the housing 10 is injection molded in a mold, stainless steel tubes (SUS) can be inserted into the mold so that the tubes 12 are integral with the separating plate 13 of the housing 10 and protrude from it.

[0046] Furthermore, a urea inlet 16 is formed in the upper protective plate 14 of the housing 10, which directs the urea to a filter to enable the filtration of the urea.

[0047] Furthermore, a circuit board is attached to the lower surface of the separating plate 13 for processing signals from a urea fill quantity sensor and a sensor for detecting an impermissible urea concentration, and the lower protective plate 15 is provided with a connector 17 for the input / output of the circuit board and a urea auxiliary connection 18 which communicates with the urea outlet opening 11.

[0048] Furthermore, a sealing cover 19 is connected to the lower protective plate 15 to hermetically seal, for example, various circuit boards and electronic components on the lower surface of the partition plate 13 and inside the lower protective plate 15. The sealing cover 19 has a vent of check valve type 19-1 to prevent condensation.

[0049] The heating device 20 uses a positive temperature coefficient (PTC) element and has, as in Fig. Figure 7 shows a frame in which a PTC element 22 is coupled to the outer circumferential section of a cylindrical heat sink 21.

[0050] In particular, a first sealing material 23 is injected over the surface of the cylindrical cooling body 21. During the injection of the first sealing material 23, a first fastening opening 24, into which the tube 12 is inserted and fastened, is formed vertically in the outer circumferential section of the cooling body 21.

[0051] In particular, the first sealing material 23 contains as in Fig. Figure 8 shows a first injected section 23-1, which is first injected over a section of the inner surface and outer circumferential surface of the cylindrical cooling body 21, which has been coupled to the PTC element 22, and a second injected section 23-2, which is then injected over the upper surface and the remaining inner circumferential surface of the cooling body 21.

[0052] This means that the first sealing material 23 of the heating device 20 is in contact with the urea in the urea tank, thus preventing the urea from penetrating the heating device 20.

[0053] The contact surface between the first injection-molded section 23-1 and the second injection-molded section 23-2 can be designed with a toothed structure 25 to increase the water resistance against urea, thereby further preventing the urea from penetrating the heat sink 21 and the PTC element 22.

[0054] As in the Fig. 3 and Fig. Figure 4 shows the electric motor 30 as a pump drive unit and includes as a mounting frame a hollow stator 33 with a coil 31 wound around its outer circumferential section and a terminal 32 installed on the top, and a second sealing material 34 is sprayed over the surface of the stator 33 including the coil 31 and the terminal 32.

[0055] When the second sealing material 34 is sprayed on, a second fastening opening is formed in the outer circumferential section of the stator 33, so that the upper end section of the tube 12, which was guided through the first fastening opening 24 in the heating device 20, is inserted into the second fastening opening 35 and fastened therein.

[0056] Similarly, the contact surface between the second sealing material 34 and the lower surface of the hollow stator 33 can be provided with a toothed structure 36 to maximize water tightness.

[0057] This means that the second sealing material 34 of the electric motor 30 is in contact with the urea in the urea tank, thus preventing the urea from entering the electric motor 30.

[0058] As in the Fig. 5, Fig. 6A and Fig. Figure 6B shows the pump driven by the electric motor for pumping urea after it has been inserted into and coupled to the stator 33 of the electric motor 30. The pump 40 contains an impeller 41, which is rotatably mounted on its top and inserted into the hollow stator 33 of the electric motor 30, and has an inlet 42 and an outlet 43 in its lower section. A pair of gears is installed in the pump 40 for forward or reverse rotation.

[0059] Since the rotor 41 can rotatably protrude upwards from the housing of the pump 40 and be exposed to the urea inside the urea tank, a third sealing material 44 can be sprayed onto the surface of the rotor 41 to avoid direct contact between the rotor 41 and the urea.

[0060] Furthermore, an E-ring 45 can be attached to the upper end of a rotating shaft protruding from the upper surface of the rotor 41 to prevent the rotor from detaching, thus preventing the rotor 41 from detaching after assembly and preventing a collision between the rotor 41 and the inner diameter of the stator 33.

[0061] Furthermore, the suction opening 42 formed in the lower section of the pump 40 is connected to a suction pipe 54 of a filter assembly 50, which is described below, and the outlet opening 43 is connected to the urea outlet opening 11 of the separating plate 13.

[0062] As in the Fig. 11 and Fig. Figure 12 shows pump 40, a gear pump in which a pair of gears 46 can be installed for forward or reverse rotation. When the gears 46 rotate forward or backward, the urea can be supplied or withdrawn.

[0063] Furthermore, in order to achieve a uniform rotation of the gears 46 by reducing the remaining high pressure when the gears 46 installed in the pump 40 rotate forwards or backwards, that is, to keep the internal pressure of the pump 40 constant, in order to reduce pulsation in the closed state of a urea dosing module, which is an injector for spraying urea to an SCR catalyst, a bypass line 47 is provided at the center of rotation of the gears 46 to discharge the urea remaining in the pump into the urea tank.

[0064] As in Fig. As shown in Figure 9, the filter assembly 50 serves to filter out foreign substances before the urea is directed from the urea tank to the pump 40, and is installed in the space between the inner diameter of the upper protective plate 14 and the outer diameter of the heating device 20 for filtering the urea, which is introduced as a horizontal flow through the urea inlet 16 in the upper protective plate 14, and for directing the urea to the pump 40.

[0065] For this purpose, the outer circumferential section of the filter assembly 50 is open for communication with the urea inlet 16 formed in the upper protective plate 14 and includes as a receiving frame a housing 51 with an upper opening structure for the filter assembly, which sits on a side section of the upper surface of the separating plate 13 and is assembled with it.

[0066] Furthermore, a filter 52 is formed on the underside of the housing 51 by overmolding for filtering out foreign substances in urea, and an upper cover 53 is attached to the top of the housing 51 for covering and sealing the filter 52.

[0067] Furthermore, the suction pipe 54 projects into the space within the housing 51 through its inner diameter section, allowing it to communicate with the space after filtration through the filter 52. The suction pipe 54 can be connected to the intake opening 42 of the pump 40 for this purpose.

[0068] As in Fig. Figure 10 shows the urea pump module for vehicles according to the present disclosure being successively fully assembled, wherein the heating device 20 is attached by inserting and securing the tubes 12 on the partition plate 13 into the respective first mounting openings 24 in the heating device 20, the filter assembly 50 is installed in the space between the inner diameter of the upper protective plate 14 and the outer diameter of the heating device 20, the electric motor 30 and the pump 40, which have been attached to each other, are inserted and arranged in a hollow section of the heating device 20, and the upper end sections of the tubes 12, which have been guided through the first mounting openings 24 of the heating device 20, are inserted into respective second mounting openings 35 in the electric motor 30 in order to fix it, whereby an E-ring is attached, which e.g.various electrical circuit boards, electrical elements and wires are attached to the lower surface of the separating plate 13, which is sealed under the protective plate 15 by connecting it to the sealing cover 19, in order to protect the electrical circuit boards, electrical elements and wires.

[0069] If the urea pump module of the present disclosure is used in the sequence described above as in Fig. As shown in Figure 17, a first rubber element 48 in ring form can be attached to the lower surface of the pump 40, which is in contact with the upper surface of the separating plate 13 to absorb vibrations, and a second rubber element 49 can be attached to the contact section between the upper surface of the cylindrical heating device 20 and the electric motor 30, which can absorb vibrations (especially perpendicular vibrations) during pump operation and dampen noise.

[0070] Although the electric motor, pump, heating element, and the like are exposed within the urea tank, when the urea pump module of the present disclosure is assembled and installed in the urea tank as described above, sealing materials are sprayed onto the surfaces of the electric motor, pump, heating element, and the like to prevent contact or ingress of the urea, thereby maintaining the watertightness of the electrical elements such as the heating element, electric motor, pump, and the like. This effectively prevents damage to the heating element, electric motor, pump, and the like, as well as operational downtime.

[0071] Furthermore, a urea fill quantity sensor 60 and a sensor for detecting an impermissible urea concentration 70 are installed at separate positions on the upper surface of the separating plate 13.

[0072] As in Fig. Figure 15 shows the urea fill level sensor 60 and the sensor for detecting an impermissible urea concentration 70 on the upper surface of the separating plate 13 installed at separate positions such that the urea fill level sensor 60 is installed for sending and receiving ultrasound waves in a vertical direction and the sensor for detecting an impermissible urea concentration 70 is installed for sending and receiving ultrasound waves in a horizontal direction.

[0073] Furthermore, the urea fill quantity sensor 60 includes a cylindrical guide 62 to guide the sending and receiving of the perpendicular ultrasonic waves, and the sensor for detecting an impermissible urea concentration 70 includes an ultrasonic wave emitter 72 and a reflector 74, which are installed opposite each other on the separating plate 13.

[0074] When the urea fill level sensor 60 emits ultrasonic waves upwards (towards the urea flow level) to detect the fill level of urea in the urea tank, the emitted ultrasonic waves, after being reflected from the urea flow level, may not be received by the urea fill level sensor 60, but may be reflected from the urea flow level to other elements (i.e., to the pump and the upper surface of the heating device) and then reflected again to the urea flow level, which may degrade the accuracy of the detection.

[0075] To solve this problem, as in Fig. Figure 16 shows a plurality of ribs 64 with a round cross-section integral from the upper surface of the first sealing material 23 injected onto the surface of the heating device 20 and from the upper surface of the second sealing material 34 injected onto the surface of the electric motor 30, in order to avoid reflection of the ultrasonic waves emitted by the urea fill quantity sensor 60 and reflected from the urea flow plane.

[0076] The operation of the urea pump module of the present disclosure with the configuration described above is described below.

[0077] When the pump 40 is driven by the electric motor 30, the urea in the urea tank is first drawn into the pump 40 by suction.

[0078] The urea in the urea tank can pass through filter 52 of filter assembly 50 before being introduced into pump 40. The urea flows laterally as described in... Fig. Figure 14 illustrates what can increase the efficiency of filtration of foreign substances.

[0079] This means that, since the filter assembly 50 is configured to filter the urea in a lateral direction (horizontal direction), the deposition of foreign substances can be avoided and consequently a disturbance of the urea flow can be prevented, and the foreign substances deposited by filtration during the urea supply can be removed and separated by the urea flow during the withdrawal due to the uniform supply and withdrawal flow path of the urea.

[0080] The urea filtered through the filter 52 then flows to the intake opening 42 of the pump 40 and through the suction pipe 54 of the filter assembly 50.

[0081] The urea introduced into the intake opening 42 of the pump 40 is then pumped out of the outlet opening 43 of the pump 40 by means of pumps, depending on the rotation of the gears in the pump, and subsequently fed through the urea outlet opening 11 in the housing 10 to the urea dosing module, which is connected to the outlet opening 43 and the urea auxiliary connection 18. The urea dosing module thus sprays the urea to the SCR catalyst.

[0082] If the urea, in the state in which the electric motor and pump are inserted into and arranged in the hollow section of the heating device 20, is frozen in winter, as in Fig. As shown in Figure 13, the heat from the heating device 20 can be transferred to the electric motor 30 and the pump 40 as well as to the urea in the urea tank, thereby effectively thawing the urea in the pump 40 and the urea in the urea tank.

[0083] As can be seen from the description above, the present revelation brings the following effects. (1) Although an electric motor, a pump, a heating device and the like are exposed inside the urea tank when a urea pump module of the present disclosure is installed in the urea tank, damage to the heating device, the electric motor, the pump and the like, as well as a disruption of their operation, can be easily prevented because a sealing material is sprayed over the surface of the electric motor, the pump, the heating device and the like to prevent contact or ingress of urea. (2) Since the heating device has a cylindrical shape and is located between the pump and a filter, the heat from the heating device can be transferred to the electric motor and pump as well as to the urea in the urea tank, thereby maximizing the de-icing effect of the urea in winter. (3) Since a bypass line is designed to maintain a constant pressure in the pump, pulsation of the pump can be prevented and uniform discharge and suction of the pump can be achieved. (4) Since a filter assembly has an improved structure that can filter the urea in a lateral direction (horizontal direction), the deposition of foreign substances can be avoided and consequently a disturbance of the urea flow can be prevented, and the foreign substances deposited by filtration during the urea feed can be removed and separated by the urea flow during the retraction because of the uniform feed and retract flow path of the urea. (5) Since a urea fill level sensor and a sensor for detecting an impermissible urea concentration using ultrasonic waves are installed in separate positions, the precision of the output of each sensor can be increased. (6) Since a rubber element or the like is attached to the contact sections between the pump and the housing and between the pump and the heating device to absorb vertical vibrations, vibration noise can be dampened. (7) Since the tubes are overmolded inside the plastic housing during its manufacture, the pump, heating device and the like can easily be assembled sequentially using the tubes. (8) With just one gear-type pump, the discharge (supply) and suction (return) of urea can be achieved by forward and backward rotation of the gears.

[0084] The disclosure has been described in detail with reference to preferred embodiments. However, it is clear to the person skilled in the art that the present disclosure can be implemented in various modifications and changes, e.g., by adding, changing, or omitting components, without deviating from the fundamentals and spirit of the disclosure, and these modifications and changes are covered by the scope of the present disclosure.

[0085] Furthermore, detailed explanations of known functions and configurations have been omitted from the descriptions of the embodiments of this disclosure where doing so would further obscure the subject matter of this disclosure. Moreover, the terms used in the above description are defined in light of the functions in the embodiments of this disclosure and may be replaced by other terms based on the intentions of users or operators, customs, or the like. Therefore, the meanings of these terms should be understood within the context of the entire content of this description. Accordingly, the above detailed description of this disclosure is not intended to limit the present disclosure by the disclosed embodiments, and the attached claims should be interpreted as encompassing other embodiments.

Claims

[1] Urea pump module for vehicles, comprising: a housing (10) comprising a partition plate (13) with a urea outlet opening (11) and a plurality of tubes (12) formed in an upper surface thereof, as well as an upper and a lower protective plate (14, 15) which are integrally formed at the upper and lower surface edge of the respective partition plate (13); a cylindrical heating device (20) comprising a first sealing material (23) which is injected over a surface of a cylindrical cooling element (21) coupled to a positive temperature coefficient (PTC) element (22), wherein the heating device (20) has a first fastening opening (24) in an outer circumferential section into which each tube (12) is inserted and fastened; an electric motor (30) comprising a second sealing material (34) which is injected over a surface of a hollow stator (33), wherein a winding runs around an outer circumferential section of the same, and a terminal is provided on its upper side, and wherein the electric motor (30) has a second mounting opening (35) in the outer circumferential section, such that an upper end section of the tube (12) which has been passed through the first mounting opening (24) is inserted into and secured in the second mounting opening (35); and a pump (40) with a rotor (41) rotatably mounted on its upper side, which is inserted into the hollow stator (33) of the electric motor (30), an inlet opening (42) and an outlet opening (43) in a lower section, and a pair of gears (46) rotatably installed therein in forward or reverse rotation, wherein in a state in which the electric motor (30) and the pump (40) are inserted and arranged in a hollow section of the heating device (20), heat from the heating device (20) is transferred to the electric motor (30) and the pump (40) as well as to the urea in the urea tank. [2] Module according to claim 1, wherein the separating plate (13) of the housing (10) has a lower surface on which a circuit board for processing signals from a urea fill quantity sensor (60) and a sensor (70) for detecting an impermissible urea concentration is attached, and the lower protective plate (15) has a connector (17) for the input / output of the circuit board and a urea auxiliary connection (18) which communicates with the urea outlet opening (11). [3] Module according to claim 1, wherein the lower protective plate (15) is connected to a sealing cover (19) which seals electronic elements on a lower surface of the separating plate (13) and in the lower protective plate (15), and the sealing cover (19) has a vent of the check valve type (19-1). [4] Module according to claim 1, wherein the first sealing material (23) has a first injection-molded section (23-1) which is first injection-molded onto a section of an inner circumferential surface and an outer circumferential surface of the cylindrical heat sink (21) coupled with the PTC element (22), and a second injection-molded section (23-2) which is then injection-molded onto an upper surface and the remaining inner circumferential surface of the heat sink (21), and a contact surface with a toothed structure (25) is provided between the first and the second injection-molded section (23-1, 23-2). [5] Module according to claim 1, wherein a contact surface with a toothed structure (25) is provided between the second sealing material (34) and a lower surface of the hollow stator (33). [6] Module according to claim 1, wherein the pump (40) includes a third sealing material (44) which is injected over a surface of the rotor (41), and an E-ring (45) is attached to the upper end of a rotating shaft which protrudes from an upper surface of the rotor (41) to prevent the rotor (41) from coming loose. [7] Module according to claim 1, wherein the gears (46) have a bypass line at their center of rotation for communication with the interior of the urea tank, the bypass line serving as a path for the reduction of the remaining high pressure when the gears (46) installed in the pump (40) rotate forward or backward. [8] Module according to claim 1, further comprising a filter assembly (50) installed in a space between the inner diameter of the upper protective plate (14) and the outer diameter of the heating device (20) to filter the urea introduced in a horizontal flow through the urea inlet (16) in the upper protective plate (14) and to direct the urea to the suction opening (42) in the pump (40). [9] Module according to claim 8, wherein the filter assembly (50) comprises: a housing (51) with an open outer circumferential section that communicates with the urea inlet formed in the upper protective plate (14), wherein the housing (51) is formed with an upper open structure for the filter assembly (50) and rests on and is assembled with a side section of the upper surface of the separating plate (13); a filter (52) formed on the underside of the housing (51) by overmolding; a tightly fitted upper cover with an upper opening in the housing (51) that covers the filter; and a suction pipe (54) which protrudes from an inner diameter section of the housing (51) and communicates with a space in the housing (51) after filtration through the filter, wherein the suction pipe (54) is connected to the intake opening (42) in the pump (40). [10] Module according to claim 1, further comprising a urea fill quantity sensor (60) and a sensor (70) for detecting an impermissible urea concentration, which are installed at separate positions on the upper surface of the separating plate (13). [11] Module according to claim 10, wherein the urea fill level sensor (60) and the sensor (70) for detecting an impermissible urea concentration on the upper surface of the separating plate (13) are installed at separate positions such that the urea fill level sensor (60) is installed for sending and receiving ultrasound waves in a vertical direction and the sensor (70) for detecting an impermissible urea concentration is installed for sending and receiving ultrasound waves in a horizontal direction. [12] Module according to claim 11, wherein the urea fill quantity sensor (60) includes a cylindrical guide (62) configured to guide the sending and receiving of the perpendicular ultrasonic waves and the sensor (70) for detecting an impermissible urea concentration includes an ultrasonic wave emitter (72) and a reflector (74) installed opposite each other on the separating plate (13). [13] Module according to claim 1, wherein the sealing material (23) injected onto the surface of the heating device (20) and the second sealing material (34) injected onto a surface of the electric motor (30) contain a plurality of ribs with a round cross-section on the upper surfaces to prevent the reflection of the ultrasonic waves emitted by the urea fill quantity sensor (60) and reflected by a urea flow plane. [14] Module according to claim 1, wherein the pump (40) includes a first rubber element (48) having a ring shape, which is attached to a lower surface of the same, which is in contact with the upper surface of the separating plate (13) to absorb vibrations, and a second rubber element (49) is attached to a contact section between an upper surface of the cylindrical heating device (20) and the electric motor (30) during assembly.

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